1. Field of the Invention
The present invention relates to a method for operating an imaging medical installation, e.g. a computed tomography or magnetic resonance installation, the installation of the type having at least one sensor and a control device with a main memory and a bulk memory.
2. Description of the Prior Art
Installations of the above type are known wherein the sensor detects measured signals from an object and supplies them to the control device, which buffer-stores the measured signals or raw signals ascertained using the measured signals online in the main memory, and wherein each buffer-stored signal contains components from a number of locations in the space and each component is dependent on a location-dependent influence factor which is determined by the object, and wherein the buffer-stored signals can be used to ascertain useful signals which respectively correspond to one of the influence factors, so that the useful signals form a three-dimensional reconstruction of the object.
Such methods of operation are general knowledge in the field of imaging technology. In particular magnetic resonance imaging installations operate according to this principle.
Magnetic resonance imaging installations produce large volumes of measured signals at a high data rate. For example, a typical volume of data is several gigabytes, which are produced at a data rate of up to 100 megabytes per second.
Conventionally, although the measured signals or the raw signals are buffer-stored in the main memory online, permanent storage is undertaken only for the reconstructed useful signals. This practice has a number of drawbacks.
For example, the data are lost if there is a voltage dip. An uninterruptible voltage supply is therefore required in order to ensure data integrity.
A situation may also arise—particularly with parallel measured signal detection by a number of sensors—in which subsequent operations for processing the useful signals further give the first indication that an unfavorable method has been chosen for ascertaining the useful signals. In this case, a repeat measurement is required, since the measured signals themselves and also the raw signals are no longer available. This is disadvantageous, particularly when it is necessary to administer a contrast agent to an object to be examined (=a human) in order to take the measurement.
It is also necessary to ascertain the useful data immediately.
Finally, the main memory is relatively expensive and often can be produced only in a limited size in an installation.